Con Edison is in the hot seat over last week’s deadly Harlem gas explosion as the feds investigate whether the company’s negligence caused the blast.

The National Transportation Safety Board has seized control of the probe into the March 12 disaster — which killed eight people — and is poring over Con Ed’s call logs and the maintenance history of the problematic gas lines, sources said Monday.

Con Ed officials were forced to sign a document agreeing not to disclose information about what took place after the leak was reported last Wednesday.

“NTSB is running the investigation. We have to refer all questions about the status of the investigation and anything that happened after 9:13 to them,” said a Con Ed spokesman, referring to the time when they were alerted to the leak.

Eric Weiss, a spokesman for the NTSB, said in an e-mail that the utility company is a “party to the investigation” and as such is not permitted to share any facts pertaining to the investigation.

Weiss said the NTSB will likely release a written update tomorrow regarding the investigation’s findings.

Crews from Con Ed could be seen pressure testing the unearthed gas main near East 117th Street and Park Avenue Monday in an effort to find where and why the gas leak occurred.

If the NTSB concludes that the aging cast-iron pipes were neglected or not properly maintained, Con Ed may be blamed for the blast.

The utility company’s president, John McAvoy, said last week that the gas mains in the area had been surveyed as recently as last summer.

Yet the NTSB, also last week, said that the soil surrounding the destroyed buildings was saturated with a higher-than-normal concentration of natural gas — suggesting that the gas had been leaking for some time.

All eight of the victims died from either burns, smoke inhalation or blunt force trauma, according to a city Medical Examiner’s Office report released last week.

George Amadeo, 42, Andreas Panagopoulos, 43, Griselde Camacho, 48 and Rosaura Barrios, 44, all died of blunt force trauma to the head and/or body.